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Apr 2, 2021
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Replace llvm_asm! with asm! #410

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9 changes: 2 additions & 7 deletions examples/intrinsics.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -6,7 +6,7 @@
#![allow(unused_features)]
#![cfg_attr(thumb, no_main)]
#![deny(dead_code)]
#![feature(llvm_asm)]
#![feature(test)]
#![feature(lang_items)]
#![feature(start)]
#![feature(allocator_api)]
Expand Down Expand Up @@ -276,14 +276,9 @@ mod intrinsics {
}

fn run() {
use core::hint::black_box as bb;
use intrinsics::*;

// A copy of "test::black_box". Used to prevent LLVM from optimizing away the intrinsics during LTO
fn bb<T>(dummy: T) -> T {
unsafe { llvm_asm!("" : : "r"(&dummy)) }
dummy
}

bb(aeabi_d2f(bb(2.)));
bb(aeabi_d2i(bb(2.)));
bb(aeabi_d2l(bb(2.)));
Expand Down
188 changes: 94 additions & 94 deletions src/arm.rs
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Expand Up @@ -9,135 +9,135 @@ use core::intrinsics;
#[cfg(not(any(target_os = "ios", target_env = "msvc")))]
#[naked]
#[cfg_attr(not(feature = "mangled-names"), no_mangle)]
pub unsafe fn __aeabi_uidivmod() {
llvm_asm!("
push {lr}
sub sp, sp, #4
mov r2, sp
bl __udivmodsi4
ldr r1, [sp]
add sp, sp, #4
pop {pc}
" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn __aeabi_uidivmod() {
asm!(
"push {{lr}}",
"sub sp, sp, #4",
"mov r2, sp",
"bl __udivmodsi4",
"ldr r1, [sp]",
"add sp, sp, #4",
"pop {{pc}}",
options(noreturn)
);
}

#[cfg(target_os = "ios")]
#[naked]
#[cfg_attr(not(feature = "mangled-names"), no_mangle)]
pub unsafe fn __aeabi_uidivmod() {
llvm_asm!("
push {lr}
sub sp, sp, #4
mov r2, sp
bl ___udivmodsi4
ldr r1, [sp]
add sp, sp, #4
pop {pc}
" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn __aeabi_uidivmod() {
asm!(
"push {{lr}}",
"sub sp, sp, #4",
"mov r2, sp",
"bl ___udivmodsi4",
"ldr r1, [sp]",
"add sp, sp, #4",
"pop {{pc}}",
options(noreturn)
);
}

#[cfg(not(target_os = "ios"))]
#[naked]
#[cfg_attr(not(feature = "mangled-names"), no_mangle)]
pub unsafe fn __aeabi_uldivmod() {
llvm_asm!("
push {r4, lr}
sub sp, sp, #16
add r4, sp, #8
str r4, [sp]
bl __udivmoddi4
ldr r2, [sp, #8]
ldr r3, [sp, #12]
add sp, sp, #16
pop {r4, pc}
" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn __aeabi_uldivmod() {
asm!(
"push {{r4, lr}}",
"sub sp, sp, #16",
"add r4, sp, #8",
"str r4, [sp]",
"bl __udivmoddi4",
"ldr r2, [sp, #8]",
"ldr r3, [sp, #12]",
"add sp, sp, #16",
"pop {{r4, pc}}",
options(noreturn)
);
}

#[cfg(target_os = "ios")]
#[naked]
#[cfg_attr(not(feature = "mangled-names"), no_mangle)]
pub unsafe fn __aeabi_uldivmod() {
llvm_asm!("
push {r4, lr}
sub sp, sp, #16
add r4, sp, #8
str r4, [sp]
bl ___udivmoddi4
ldr r2, [sp, #8]
ldr r3, [sp, #12]
add sp, sp, #16
pop {r4, pc}
" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn __aeabi_uldivmod() {
asm!(
"push {{r4, lr}}",
"sub sp, sp, #16",
"add r4, sp, #8",
"str r4, [sp]",
"bl ___udivmoddi4",
"ldr r2, [sp, #8]",
"ldr r3, [sp, #12]",
"add sp, sp, #16",
"pop {{r4, pc}}",
options(noreturn)
);
}

#[cfg(not(target_os = "ios"))]
#[naked]
#[cfg_attr(not(feature = "mangled-names"), no_mangle)]
pub unsafe fn __aeabi_idivmod() {
llvm_asm!("
push {r0, r1, r4, lr}
bl __aeabi_idiv
pop {r1, r2}
muls r2, r2, r0
subs r1, r1, r2
pop {r4, pc}
" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn __aeabi_idivmod() {
asm!(
"push {{r0, r1, r4, lr}}",
"bl __aeabi_idiv",
"pop {{r1, r2}}",
"muls r2, r2, r0",
"subs r1, r1, r2",
"pop {{r4, pc}}",
options(noreturn)
);
}

#[cfg(target_os = "ios")]
#[naked]
#[cfg_attr(not(feature = "mangled-names"), no_mangle)]
pub unsafe fn __aeabi_idivmod() {
llvm_asm!("
push {r0, r1, r4, lr}
bl ___aeabi_idiv
pop {r1, r2}
muls r2, r2, r0
subs r1, r1, r2
pop {r4, pc}
" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn __aeabi_idivmod() {
asm!(
"push {{r0, r1, r4, lr}}",
"bl ___aeabi_idiv",
"pop {{r1, r2}}",
"muls r2, r2, r0",
"subs r1, r1, r2",
"pop {{r4, pc}}",
options(noreturn)
);
}

#[cfg(not(target_os = "ios"))]
#[naked]
#[cfg_attr(not(feature = "mangled-names"), no_mangle)]
pub unsafe fn __aeabi_ldivmod() {
llvm_asm!("
push {r4, lr}
sub sp, sp, #16
add r4, sp, #8
str r4, [sp]
bl __divmoddi4
ldr r2, [sp, #8]
ldr r3, [sp, #12]
add sp, sp, #16
pop {r4, pc}
" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn __aeabi_ldivmod() {
asm!(
"push {{r4, lr}}",
"sub sp, sp, #16",
"add r4, sp, #8",
"str r4, [sp]",
"bl __divmoddi4",
"ldr r2, [sp, #8]",
"ldr r3, [sp, #12]",
"add sp, sp, #16",
"pop {{r4, pc}}",
options(noreturn)
);
}

#[cfg(target_os = "ios")]
#[naked]
#[cfg_attr(not(feature = "mangled-names"), no_mangle)]
pub unsafe fn __aeabi_ldivmod() {
llvm_asm!("
push {r4, lr}
sub sp, sp, #16
add r4, sp, #8
str r4, [sp]
bl ___divmoddi4
ldr r2, [sp, #8]
ldr r3, [sp, #12]
add sp, sp, #16
pop {r4, pc}
" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn __aeabi_ldivmod() {
asm!(
"push {{r4, lr}}",
"sub sp, sp, #16",
"add r4, sp, #8",
"str r4, [sp]",
"bl ___divmoddi4",
"ldr r2, [sp, #8]",
"ldr r3, [sp, #12]",
"add sp, sp, #16",
"pop {{r4, pc}}",
options(noreturn)
);
}

// The following functions use weak linkage to allow users to override
Expand Down
1 change: 0 additions & 1 deletion src/lib.rs
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Original file line number Diff line number Diff line change
@@ -1,7 +1,6 @@
#![cfg_attr(feature = "compiler-builtins", compiler_builtins)]
#![cfg_attr(not(feature = "no-asm"), feature(asm))]
#![feature(abi_unadjusted)]
#![cfg_attr(not(feature = "no-asm"), feature(llvm_asm))]
#![cfg_attr(not(feature = "no-asm"), feature(global_asm))]
#![feature(cfg_target_has_atomic)]
#![feature(compiler_builtins)]
Expand Down
96 changes: 49 additions & 47 deletions src/x86.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -16,26 +16,27 @@ use core::intrinsics;
))]
#[naked]
#[no_mangle]
pub unsafe fn ___chkstk_ms() {
llvm_asm!("
push %ecx
push %eax
cmp $$0x1000,%eax
lea 12(%esp),%ecx
jb 1f
2:
sub $$0x1000,%ecx
test %ecx,(%ecx)
sub $$0x1000,%eax
cmp $$0x1000,%eax
ja 2b
1:
sub %eax,%ecx
test %ecx,(%ecx)
pop %eax
pop %ecx
ret" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn ___chkstk_ms() {
asm!(
"push %ecx",
"push %eax",
"cmp $0x1000,%eax",
"lea 12(%esp),%ecx",
"jb 1f",
"2:",
"sub $0x1000,%ecx",
"test %ecx,(%ecx)",
"sub $0x1000,%eax",
"cmp $0x1000,%eax",
"ja 2b",
"1:",
"sub %eax,%ecx",
"test %ecx,(%ecx)",
"pop %eax",
"pop %ecx",
"ret",
options(noreturn, att_syntax)
);
}

// FIXME: __alloca should be an alias to __chkstk
Expand All @@ -47,10 +48,11 @@ pub unsafe fn ___chkstk_ms() {
))]
#[naked]
#[no_mangle]
pub unsafe fn __alloca() {
llvm_asm!("jmp ___chkstk // Jump to ___chkstk since fallthrough may be unreliable"
::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn __alloca() {
asm!(
"jmp ___chkstk", // Jump to ___chkstk since fallthrough may be unreliable"
options(noreturn, att_syntax)
);
}

#[cfg(all(
Expand All @@ -61,27 +63,27 @@ pub unsafe fn __alloca() {
))]
#[naked]
#[no_mangle]
pub unsafe fn ___chkstk() {
llvm_asm!("
push %ecx
cmp $$0x1000,%eax
lea 8(%esp),%ecx // esp before calling this routine -> ecx
jb 1f
2:
sub $$0x1000,%ecx
test %ecx,(%ecx)
sub $$0x1000,%eax
cmp $$0x1000,%eax
ja 2b
1:
sub %eax,%ecx
test %ecx,(%ecx)

lea 4(%esp),%eax // load pointer to the return address into eax
mov %ecx,%esp // install the new top of stack pointer into esp
mov -4(%eax),%ecx // restore ecx
push (%eax) // push return address onto the stack
sub %esp,%eax // restore the original value in eax
ret" ::: "memory" : "volatile");
intrinsics::unreachable();
pub unsafe extern "C" fn ___chkstk() {
asm!(
"push %ecx",
"cmp $0x1000,%eax",
"lea 8(%esp),%ecx", // esp before calling this routine -> ecx
"jb 1f",
"2:",
"sub $0x1000,%ecx",
"test %ecx,(%ecx)",
"sub $0x1000,%eax",
"cmp $0x1000,%eax",
"ja 2b",
"1:",
"sub %eax,%ecx",
"test %ecx,(%ecx)",
"lea 4(%esp),%eax", // load pointer to the return address into eax
"mov %ecx,%esp", // install the new top of stack pointer into esp
"mov -4(%eax),%ecx", // restore ecx
"push (%eax)", // push return address onto the stack
"sub %esp,%eax", // restore the original value in eax
"ret",
options(noreturn, att_syntax)
);
}
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